1. Field of the Invention
The present invention relates to an automotive display apparatus and more particularly to an automotive display apparatus wherein light from a display of an indicator is passed through a transmissive first reflector plate onto a second reflector plate, reflected by the second reflector plate toward the first reflector plate, and then further reflected by the first reflector plate toward an eye range of a driver by way of a face plate disposed between the first reflector plate and the eye range, which face plate is inclined toward the side opposite to the eye range. An image of the indicator display may be viewed from the eye range as a remote virtual image within a viewing area on the first reflector plate. The above-mentioned construction provides a good remote display effect without increasing the overall size of the apparatus.
2. Description of the Prior Art
An example of such an automotive display apparatus is shown in FIG. 2. In the figure, denoted 11 is a dashboard, in which is installed a light-emitting indicator 12, such as a liquid crystal display or a fluorescent display tube, for displaying thereon information on driving conditions such as a speed of a vehicle. On the display surface side of the indicator 12 is disposed a transmissive reflector plate 13, which allows the light of display from the indicator 12 to pass therethrough. Opposingly positioned to the indicator 12 by way of the reflector plate 13 is a mirror 14.
At the front of the dashboard 11 is provided a face plate 15 having a concave configuration for the protection of the reflector plate 13 and mirror 14 and for keeping them free from dust, the reflector plate 13 and mirror 14 otherwise tending to collect dust to deteriorate the quality and recognizability of the image displayed. The face plate 15 is, for example, formed of a dark color transparent smoked acrylic resin and is inclined in a direction opposite to the driver side such that the center O.sub.1 of the circle defined by the curvature of the face plate 15 is located upwardly on the driver side.
In order to keep ambient light from entering into the indicator 12, a hood 11a is provided to the dashboard 11 and a shading plate 16 is provided so as to extend between the reflector plate 13 and the indicator 12.
When the light of display is emitted from the indicator 12, it passes through the reflector plate 13 and is totally reflected by the mirror 14. The thus totally reflected light is then further reflected by the reflector plate 13 toward the eye range 21 on the driver's seat side from inside which the driver can recognize the image displayed.
As a result, when the reflector plate 13 is looked in from the eye range 21, the image of the indicator display is viewed as a virtual image X in a view area A.sub.1 behind the reflector plate 13. The view area A.sub.1 is defined in the figure by a first line that passes through the upper end 21U of the eye range 21 and the lower end of the mirror 14 reflected in the reflector plate 13 and a second line that passes through the lower end 21D of the eye range 21 and the upper end of the mirror 14 reflected in the reflector plate 13.
The virtual image X is formed inside the boundary of the mirror 14 reflected in the reflector plate 13 and at a position remote by a distance corresponding to the overall length of the light path, thus providing a good remote display effect.
In this instance, however, part of the light from a display of the indicator 12 is directly passed through the reflector plate 13 onto the face plate 15 at its rear upper portion A.sub.2. The rear upper portion A.sub.2 is defined in the figure above the intersection of the face plate 15 with a line drawn through the upper edge of the shading plate 16 and the right side of the display surface of the indicator 12.
The light of display directly incident on the rear upper portion A.sub.2 of the face plate 15 is reflected thereby to form a virtual image X.sub.1, which in turn is reflected by the reflector plate 13 to form a virtual image X.sub.2. The virtual image X.sub.2 is further reflected by the mirror 14 to form a virtual image X.sub.3, and the virtual image X.sub.3 by the reflector plate 13 to form a virtual image X.sub.4, which is located inside the view area A.sub.1.
Consequently, when viewed from the eye range 21, the virtual image X.sub.4 is recognized as a ghost below the virtual image X in the viewing area on the reflector plate 13, as shown in FIG. 3, resulting in deterioration of the quality and recognizability (or contrast) of the virtual image X.
One of the countermeasures employed in a conventional automotive display apparatus is to install the indicator 12 at a lowered position in the dashboard 11 such that the light of display from the indicator 12 does not fall on and is not reflected by the rear upper portion of the face plate 15. This countermeasure, however, requires an extra space and results in restriction of a freedom in designing. An alternative countermeasure is to apply the rear of the face plate 15 where the light of display is directly incident with AR coating (non-reflective coating) so as to reduce the light reflected thereby. This countermeasure, however, is costly.